Researchers and engineers are continually striving to improve the performance, efficiency, quality, etc. of optoelectronic devices, such as light-emitting diodes (LEDs), laser diodes (LDs), and other light-emitting devices, as well as create lower cost light-emitting devices, and devices emitting in portions of the electromagnetic spectrum that currently lack high-quality, low-cost solutions, such as in the case with the so-called “green gap” that exists for green-light-emitting semiconductor-based LEDs and LDs.
Photoluminescent materials have been used as optical gain media for various light-emitting devices. However, the quantity of such materials used in many of these devices and the increased complexity of some of these devices make them more expensive than desired. In addition, conventional usage of phosphorescent materials has not solved problems that continue to exist, such as the green gap noted above.